Electromagnetic device.



0. w. DUNHAM. ELECTROMAGNETIC DEVICE.

APPLICATION FILED SEPT. 12, 19M- Patented Feb. 13, 1917.

FIG. 1

FIG. 2

WITNESSES UNITED STATES PATENT OFFICE.

CHARLES W. DUNHAM, OF SWISSVALE,

PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

ELECTROMAGNETIC DEVICE.

Application filed September 12. 1914.

To all whom it may concern:

Be it known that I, CHARLES IV. DUNLIAM, a citizen of the United States, residing at Swissvale, in the county of Allegheny and State of Pennsylvania, have invented cer tain new and useful Improvements in Electromagnetic Devices, of which the following is a specification.

My invention relates to electromagnetic devices.

I will describe one form of device embodying my invention, and will then point out the novel features thereofin claims.

In the accompanying drawing, Figure 1 is a view showing in perspective, one form of electromagnetic device en'ibodying my invention. Fig. 2 is a view showing in side elevation a portion of the device shown in fieferring first to Fig. 1, the device in the form here shown comprises a field member A and a movable armature B of magnetizable material. The field A comprises two L- shaped members of magnetizable material each having a longer leg 1 or 1 and a shorter leg 2 or 2. The longer legs 1, 1 are par allel, and the shorter legs 2, 2 are also parallel but point in opposite directions and are separated by a spacing member 3 of magnetizable material so that the legs 1 and 1 are offset in the direction of the length of the spacing member and also in the direction in which legs 2 and 2 point. Attached to the leg 1 at the end opposite to the spacing memher 3 is a pole-niece t of magnetizable material having a concaved pole-face 6 facing in the same direction as the leg 2; and attached to the leg 1 at the end opposite to the spac' ing member 3 is a similar pole-piece 4f hav ing a similar concaved pole-face 6 facing in the direction opposite to pole-face 6. It will be seen therefore that by virtue of the construction of the core, the concaved faces 6 and 6* are offset from each other instead of being oppositely disposed as is usual in devices of this character.

The legs 1, 1 are provided with windings 11 which are connected with a battery 13 and a circuit controller 14, so that the field A is energized or not according as circuit controller 14 is closed or open. This circuit controller may be operated by any desired means, but such means forms no part of my invention, hence is not shown herein.

The armature B, as here shown, is of the Specification of Letters Patent.

Patented Feb. 13, 1917. Serial No. 861,379.

Z-type, but the two legs 9 and 9 of the are separated and offset from each other so that they are in operative relation respectively to the concave pole-faces 6 and 6. As here shown, the two legs 9 and 9 are attached by screws 15 to a shaft 10 of magnetizable material, which shaft is provided with knife-edge bearings 21 adapted to rock on suitable supports not shown in the drawing. terweight 20 which tends to cause rotation in clockwise direction as the device is viewed in the drawing, and the movement of the armature in response to the action of this counterweight is limited by a fixed stop 5 located in the path of the counterweight. The legs 9 and 9 are so arranged on the shaft 10 that when the counterweight 20 rests on the stop 5, the outer edge of leg 9 is adjacent the upper edge of pole-face 6 and the outer edge of leg 9 is adjacent the lower edge of pole-face 6'. This is shown more clearly in Fig. 52. Then when winding 11 is energized, leg 9 is drawn downwardly by pole-piece 4e, and leg 9 is drawn upwardly by pole-piece l so that the armature is swung in counter-clockwise direction against the action of counterweight 20. In accordance with usual practice the center of shaft 10 is at the center of curvature of faces 6 and 6", but the center of curvature of leg 9 is preferably slightly to the right of the center of shaft 10 so that as the armature swings in counter clockwise direction the air gap between leg 9 and pole-face 6 is gradually reduced. and for a similar reason the center of curvature of leg 9 V the left of the center of shaft 10. The angle through which the armature is thus swung is limited by the engagement of a shoulder 16 on leg 9 with a surface 7 on pole-piece 4., and by the engagement of a similar shoulder 16" on leg 9 with a similar surface 7 on pole-piece 4*. These shoulders 16 and 16" serve also as auxiliary armatures to hold the armature B positively in the extreme position to which it is moved by the field A. In accordance with usual practice, the shoulders 16 and 16 are prevented from aetual contact with surfaces 7 and 7 by core pins 8, in order to prevent sticking of the armature due to residual magnetism: as here shown, these core pins are located in the surfaces 7 and 7".

It will now be seen that, contrary to the is preferably slightly to iii oencli'sien e. I psmeluir cleviee ll i v 1 1CD. el e ennm'un'c B 'Qlie usual construcile'c, the leg 9 18 no" min is i i 1; *n shown time is encecl by pole-piece e, and the leg 9 is not influenced by pole-piece .1-; fillet is, when the einrietule occupies the extreme positien to which is moi'eel by the counterweight (as shown in 2), there is no tendency es in the o1."clinm;y ocnslxmlol-imi, Pele-p ece l to exert e turning eil'oi't on aim cling]; te relate the armature in eloclm'ise direction, and ei 1il:u'ly there is no tencleuc for the pole-piece to exe'srt a. turning; ell'erl; m

szm'zedireclion on arm 9. By 'vii'lwue P foie feet, the Mmeiure may be caused to es llate thieugh a considerably greater angle ll'iun is possible with the usual construction oi ale vices ef' cliemc'tei'. That is, Ni ii the "west angle of oscilesusl constrnciion the g1 letion We can be sem'esecl in practice 15 about we, cause if the 0f the are made longer men this filmy extend into the field of vile opposite poiepieces when the arm-mere occupies its me cleenogir etl posimcn, and the armaiure will ijllOl'OfOlG not be oved out of this position. under the iuof magnetic ectien. ln e device ceneel in accordance Willi my inventiem lmvzwzerz, Qllii armature legs 9 eml 5 may eK- tend through arcs of 90 and the pole-faces 6 aml 6 Hey likewise ezzlencl through 96, osoil zillion of Elie armature through an angle of 90 may readily be sub-mineclv Greater angles of oscillation can lie secures if desire? by mek'ng illlfi pole feces eiicl "the legs 01 the great than 90 in lQ-J' :lli.

Devices embcdyiing my inventien may be employed for any purpose fer "which oscillation of i'zlie ei'inebi re through e compiler lively large angle is desirable. They are especially adapted. for use the ecmzeling inc-tors for indicators em iloyecl in railway signaling. An inclicetor of this usiially compi'ises a miniature semaphore which is moved, from horizontal posi ion to other positiem an -I to conform with mocler 'i railway signaling preclziee it isfrequen'tly clesirelile time the leitei' 'posifileii be vertical; hence the sen'mplioie must move llueugli. angle el 96". l i electromagnetic (lewiees e1? type have been empleyee in such indicators it as been necessary lo inleipose e liuk between the armature encl clie Sli1E")ll019,

the Z'e'rinatm'e or to provide ether cquiveleiilv men for securing e greater up e of lllair u 01 lime semaphore ime oi 'she mine", a device embodying my invenui '1 s ployerl for this purpose lioweve 3, if,

icled "zfiliei ilie ermeimre swings through. an angle of 90 21ml the semaphore may then b attache 5i. [lire ly to the maxim lure, thus avoiding a mu plying meclie nism of any kind. This is iiicliceleil in l 3 ll, wherein e semaphore l? is etteci l ii- TfiCilly to an. ell-(l when 0 ecsts against the shop a"), tie semaphore l; 1s nor mental, and the? when the (lQVlCG is energized, *tlic flllfliL- ture 90 in C(Nlllllii-(JlOClUVlS cliceeturn so elm: the si'ainapliorc is then vertical. The (l0? (l miem sicn oli 1e seumplmi'e is 'tlu-ss secured by it twice of slmnle constructien, requiring no links 02! other motionmul'biplying menus.

is unclers coal Haul; ll). ilie practice cf my invention the entire device will usually be iuclese! in a suitable casing and J the seinepluu'e '12 will be lOCillQil iin fi'Olle oi? :1 face or l which obscures the remeiiv (l9? of the device. The casing; mul cliul omitted from the drawing to aveiil eem-- PlICHl lOD,

have herein shown end. (lie-- flersteoil tl'ur various fivulfiois )2 lie iruule scope m be epeenclecl imiting iifi'oiei ifE. elecix'romeemetic 0 device compiising a ile'd member having two eoiiiczwe pole-- :iziees facin in opposite clirec'bieiis out 0e fa m each other along 'bhe axis of curve,- ture of said ele-feces, e. having its We alone axis 5) that obey :1 in. e: e sairl pele 'lece 1y,

ice comprising,

member We conceive pole laces lacing in o eireeticns eutofi sol; fvom eecli Otllfil aloieg axis of curve;-

ture of seicl pelefe .i 1 cl eael olefee; being sulistein i 1n leng illlil Iii-armature along; cmiiwe 1' tively, the are of each {lflifl'l re le being substaii' ially 90 in length, whereby .ae er mature is cep ole c" eseilleiien'thieug'i an angle subs" 99.

i 4 L 4-. An electromagnetic device comprising a fielc having two concave poleeg in o pcsiae directions but off" 1e en la other along "the axis of curvz pole-feces, end. a Z-ermature 2 (awe legs along "the saicl axle so they in epeietive relation eue form of electrei'negneic to said pole-faces respectively, said legs being so disposed that the outer edge of one leg is adjacent one edge of its pole-face when the outer edge of the other leg is adjacent the opposite edge of the other pole-face.

5. An electromagnetic device comprising a field member and an armature mounted to oscillate, said field member having two pole-pieces offset from each other along the axis of oscillation of said armature, and said armature having two members ofl"-set 7 along the said axis so that they are in operative relation to said pole-pieces respec-. tively, whereby each armature member 1s influenced by the corresponding pole-piece but not by the other pole-piece.

6. An electromagnetic device comprising a field member having two concave polemature away from the position to which it is drawn by said field member. 1 In testimony whereof I aflix my signature in presence of two witnesses.

CHARLES WV. DUNHAM. Witnesses:

A. HERMAN WEGNER, ALBERT C. NOLTE. 

